1. Field of the Invention
This invention relates to a connector device for electrically connecting relatively rotatable members to each other.
2. Description of the Related Art
Connector devices for electrically connecting relatively rotatable members include, for example, a connector device for use in an air bag system mounted to a steering apparatus of an automobile.
In this type of connector devices, a flexible flat cable (belt-shaped transmission line) including a plurality of electrical conductors covered with an insulating material is wound in spiral form and housed in rotatable and fixed cases which are rotatable relative to each other, such that a relative rotation of these cases is permitted as the flat cable coils or uncoils. The flat cable is electrically connected to devices arranged outside of the connector device.
In such connector devices, therefore, when the flat cable is to be connected to devices outside the connector device, lead wires or an electric connector such as a connector housing, for example, is previously connected to an end of the flat cable, and the flat cable is housed in the cases, with the lead wires or connector housing located outside of the cases. Alternatively, after the flat cable is housed in the cases, an end thereof is extended to the outside of the connector device and connected to an external device via a special electric connector, or the electrical conductors of the flat cable are connected respectively to lead wires which are connected to an external device via an electric connector.
To connect the flat cable to a device outside the connector device, if, for example, lead wires or an electric connector is attached to the flat cable before the cable is housed in the cases, as mentioned above, handling of the flat cable is troublesome, and in some cases, the flat cable is bent when handled, thus forming a bend in the flat cable. In connector devices wherein a spirally wound flat cable is housed in cases and a smooth rotation of the cases is permitted by coiling and uncoiling of the flat cable, such a bend in the flat cable hinders the smooth rotation. Therefore, the flat cable must be handled with great care, and this hinders the mechanization of the assembling of connector devices.
On the other hand, in the case of connecting an electric connector or lead wires to an end of the flat cable after the flat cable is housed in the cases, the cases of the connector device may be rotated, and the order of assembling processes is restricted. Accordingly, the number of processes required for the assembling of the connector device cannot be reduced, and the assembling work cannot be mechanized or automated, requiring man power and making the work complicated.